1. Field of the Invention
This invention relates generally to an exercise device. More particularly, the invention concerns an exercise device permitting a user to perform alternatively a stair stepping exercise or a cross country skiing exercise, or to perform a combined stair stepping exercise and a cross country skiing exercise.
2. Description of the Prior Art
Heretofore, various exercise devices have been provided to permit a user to perform a stair stepping exercise which simulates the climbing of stairs. Also, various exercise devices have been provided to permit a user to perform a cross country skiing exercise which simulates cross country skiing. However, none of the exercise devices heretofore have permitted in a single exercise machine, the simultaneous performance of a stair stepping exercise and a cross country skiing exercise. No prior exercise device has allowed a user to change the exercise he is doing while on the machine from stair climbing to cross country skiing to a bicycle-like motion to a backward walk motion, all without mechanical adjustment of the machine.
For example, U.S. Pat. No. 3,970,302 dated Jul. 20, 1976, shows an exercise device in which a pair of foot supports are mounted for movement along an inclined track to simulate stair climbing. A pair of shock absorbers connected to the foot supports resist downward movement resulting from a downward force exerted by the feet of a user and provide upward return movement of the foot supports to a predetermined position. There is no showing of an exercise movement simulating cross country skiing.
U.S. Pat. No. 4,685,666 dated Aug. 11, 1987, likewise shows an exercise device to simulate a climbing or stair stepping motion, but such exercise device does not provide a cross country skiing exercise.
U.S. Pat. No. 4,733,858 dated Mar. 29, 1988, shows a multi-purpose exercise device which may be utilized to perform various exercises. The device is used in a first position to practice climbing such as climbing steps. The device is adjusted to a second position to simulate a skating motion. There is no provision for performing a climbing exercise and a skating exercise simultaneously with the device remaining in one position.
U.S. Pat. No. 5,000,442 dated Mar. 19, 1990, shows a cross country ski simulator in which foot supports are mounted for generally horizontal back and forth movement with manually gripped handles controlling the movement of the foot supports and providing a resistance to the movement of the foot supports. Such ski simulator does not provide a simulated climbing or stair stepping exercise performed simultaneously with the cross country skiing exercise.
U.S. Pat. No. 5,195,935 dated Mar. 23, 1993 shows an exercise device in which the platform of the exercise machine is adjustable in inclination to an infinite number of angles by manipulation of switch means on a control panel for actuation of a motor. Thus a user is required to actuate a switch to change the inclination of the machine.